Finally, conditional analyses of variants within the MHC locus revealed at least three additional susceptibility loci that are associated with MS risk independent of the HLA-DRB1*1501 allele: while the class I allele HLA-A*0201 showed additional protective effects, class II alleles DRB1*0301 (or DQB1*0201, since the signals could not be separated) as well as DRB1*1303 conferred further risk effects (6). Here, HLA-DRB1 is linked to myeloid sarcoma.